A roof constituting an upper part of a vehicle body includes left and right roof rails and a roof panel supported at left and right ends thereof by the left and right roof rails. The left and right roof rails and the left and right ends of the roof panel are vertically overlapped on each other, respectively, and joined together by spot welding. Upwardly opened grooves are formed at joint portions where the left and right roof rails and the left and right ends of the roof panel are joined together, which allow spot welding operation to be performed thereon in the vertical direction. The grooves are covered by decorative moldings, so that welding traces formed by spot welding on bottoms of the grooves are concealed by the decorative moldings, whereby an external appearance of the vehicle is improved. However, from a viewpoint of reducing the number of required parts in the vehicle body, it is preferable that such decorative moldings be eliminated.
A vehicle roof without such decorative moldings is disclosed, for example, in Patent Literature 1. The vehicle roof of Patent Literature 1 includes a frame-like inner roof member provided between a roof panel and left and right roof rails. The inner roof member has stepped sections on left and right ends thereof formed in a stepped shape to be lowered outward by one step. The stepped sections are overlapped on the left and right roof rails and joined thereto by spot welding. Upwardly opened grooves are formed at joint portions where the left and right ends of the inner roof member and the left and right roof rails are joined together. Bottoms of the grooves are formed by lowest surfaces of the stepped sections. The roof panel is mounted over the inner roof member so as to cover most parts of the grooves.
However, although the most parts of the grooves are covered by the roof panel, the residual parts of the grooves that are not covered are conspicuous as unnecessary gaps. Thus, there is room for further improvement for enhancing the external appearance of the vehicle. Further, amounts of the gaps formed between left and right ends of the roof panel and the left and right roof rails have to be adequately controlled.